1. Field of the Invention
The present invention relates to a scanning module having an adjustable height, and more particularly to a CIS scanning module which may adjust the assembly height to satisfy the scanning requirements.
2. Description of the Related Art
A scanner may include the scanner of a CCD module and the scanner of a CIS module. The CIS module has a smaller view depth, but is easily made to satisfy the requirements of the light, thin, short and small product. Thus, the CIS module plays an important role in the market.
The CIS module has a smaller view depth. Thus, in design and fabrication, the document to be scanned is smoothly rested on the top of the glass window of the scanner, and the CIS module is closer to the glass window of the scanner, thereby obtaining the parameters of design and fabrication.
For the reflective document, the reflective document may be smoothly rested on the top of the glass window of the scanner, to satisfy the parameters of design and fabrication. Thus, the scanner of a CIS module may be used to scan the reflective document normally.
For the transparency, the negative sheet may be scanned. The negative sheet does not have an outer frame. Thus, if the negative sheet is smoothly rested on the top of the glass window of the scanner and is mated with a proper light source, the negative sheet may be scanned.
For the transparency of the positive sheet, such as the slide, the positive sheet cannot be scanned on the scanner of a conventional CIS module. Usually, the positive sheet has an outer frame which has a determined thickness. Thus, when the positive sheet is placed on the top of the glass window of the scanner, a small distance is formed between the positive sheet and the glass window of the scanner. Thus, the distance between the positive sheet and the glass window of the scanner is greater than the original parameters of design and fabrication. In addition, the CIS module has a smaller view depth. Thus, when the scanner of a conventional CIS module is scanning the positive sheet, the scanning will obtain a vague image.
In the recent market, the CIS scanner only can provide scanning of the reflective document, and the CIS scanner cannot be used to scan the transparency. Thus, the usage of the CIS scanner is limited even it may satisfy the requirements of the light, thin, short and small product.